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==============================================================================
 MIXER REGISTERS
------------------------------------------------------------------------------
 000h       Reset                                       Write       SBPro
 001h       Status                                      Read        SBPro
 002h       Master Volume                               Read/Write  SBPro Only
 004h       DAC Level                                   Read/Write  SBPro
 006h       FM Output Control                           Read/Write  SBPro Only
 00Ah       Microphone Level                            Read/Write  SBPro
 00Ch       Input/Filter Select                         Read/Write  SBPro Only
 00Eh       Output/Stereo Select                        Read/Write  SBPro Only
 022h       Master Volume                               Read/Write  SBPro
 026h       FM Level                                    Read/Write  SBPro
 028h       CD Audio Level                              Read/Write  SBPro
 02Eh       Line In Level                               Read/Write  SBPro
 030h       Master Volume Left                          Read/Write  SB16
 031h       Master Volume Right                         Read/Write  SB16
 032h       DAC Level Left                              Read/Write  SB16
 033h       DAC Level Right                             Read/Write  SB16
 034h       FM Level Left                               Read/Write  SB16
 035h       FM Level Right                              Read/Write  SB16
 036h       CD Audio Level Left                         Read/Write  SB16
 037h       CD Audio Level Right                        Read/Write  SB16
 038h       Line In Level Left                          Read/Write  SB16
 039h       Line In Level Right                         Read/Write  SB16
 03Ah       Microphone Level                            Read/Write  SB16
 03Bh       PC Speaker Level                            Read/Write  SB16
 03Ch       Output Control                              Read/Write  SB16
 03Dh       Input Control Left                          Read/Write  SB16
 03Eh       Input Control Right                         Read/Write  SB16
 03Fh       Input Gain Control Left                     Read/Write  SB16
 040h       Input Gain Control Right                    Read/Write  SB16
 041h       Output Gain Control Left                    Read/Write  SB16
 042h       Output Gain Control Right                   Read/Write  SB16
 043h       Automatic Gain Control (AGC)                Read/Write  SB16
 044h       Treble Left                                 Read/Write  SB16
 045h       Treble Right                                Read/Write  SB16
 046h       Bass Left                                   Read/Write  SB16
 047h       Bass Right                                  Read/Write  SB16
 080h       IRQ Select                                  Read/Write  SB16
 081h       DMA Select                                  Read/Write  SB16
 082h       IRQ Status                                  Read        SB16

------------------------------------------------------------------------------
 000h       Reset                                       Write       SBPro

    DESCRIPTION
     Resets mixer to default settings.

    PROCEDURE
      a) Load index register
      b) Wait 100s
      c) Write reset stop

    RESET BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Reset Stop (0)
       |   |   |   |   |   |   \------ Reserved   (0)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    NOTES
     * Defaults documented for each register (SBPro, SB16)
------------------------------------------------------------------------------
 001h       Status                                      Read        SBPro

    DESCRIPTION
     Contains previously selected register value.

    STATUS BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Mixer Data Register value
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------


    NOTES
     * SoundBlaster 16 sets bit 7 if previous mixer index invalid.
     * Status bytes initially 080h on startup for all but level bytes (SB16)
------------------------------------------------------------------------------
 002h       Master Volume                               Read/Write  SBPro Only

    VOLUME BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 |[4]| 3 | 2 | 1 |[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Reserved (1)
       |   |   |   |   |   |   \------ Right Master Volume bit 3-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Reserved (1)
       |   |   \---------------------- Left  Master Volume bit 3-1 (SBPro)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     099h, N/A

    NOTES
     * Same as register 022h selection.

    SEE ALSO
     022h   Master Volume                       Read/Write
     -----------------------------------------------------
     030h   Master Volume Left                  Read/Write
     031h   Master Volume Right                 Read/Write
------------------------------------------------------------------------------
 004h       DAC Level                                   Read/Write  SBPro

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Right DAC Level bit  0  (SB16, SBPro=1)
       |   |   |   |   |   |   \------ Right DAC Level bit 3-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Left  DAC Level bit  0  (SB16, SBPro=1)
       |   |   \---------------------- Left  DAC Level bit 3-1 (SBPro)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     099h, 0CCh

    NOTES
     * Mixer detection can be accomplished by looking for this register index.
     * SoundBlaster 16 will automatically update registers 031h and 032h,
        transferring bits 7-4 and setting bit 3.

    SEE ALSO
     032h   DAC Level Left                      Read/Write
     033h   DAC Level Right                     Read/Write
------------------------------------------------------------------------------
 006h       FM Output Control                           Read/Write  SBPro Only

    CONTROL BYTE
     /===v===v===v===v===v===v===v===\
     I[7]| 6 | 5 |[4]| 3 | 2 | 1 |[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Reserved (1)
       |   |   |   |   |   |   \------ FM Level (bits 3-1, see notes)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Reserved (1)
       |   |   \----------------------- FM Left  Channel (0 = On, 1 = Off)
       |   \--------------------------- FM Right Channel (0 = On, 1 = Off)
       \------------------------------- Reserved (0)

    DEFAULT
     019h, N/A

    NOTES
     * FM level controls both channels.
     * If only one channel is active, the inactive channel's voices will
        be routed through the active one.
     * SoundBlaster Pro will automatically update register 026h,
        transferring source bits 3-0 to destination bits 7-4 and 3-0.

    SEE ALSO
     026h   FM Level                            Read/Write
     -----------------------------------------------------
     034h   FM Level Left                       Read/Write
     035h   FM Level Right                      Read/Write
------------------------------------------------------------------------------
 00Ah       Microphone Level                            Read/Write  SBPro

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I[7]|[6]|[5]|[4]|[3]| 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Microphone Level bit  0  (SB16, SBPro=0)
       |   |   |   |   |   |   \------ Microphone Level bit 2-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Reserved (0)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     011h, 000h

    SEE ALSO
     03Ah   Microphone Level                    Read/Write
------------------------------------------------------------------------------
 00Ch       Input/Filter Select                         Read/Write  SBPro Only

    SELECT BYTE
     /===v===v===v===v===v===v===v===\
     I[7]|[6]| 5 |[4]| 3 | 2 | 1 |[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Reserved (1)
       |   |   |   |   |   |   \------ Input Select (0 = Microphone,
       |   |   |   |   |   \---------                1 = CD Audio, 3 = Line In)
       |   |   |   |   \--------------- Frequency (0 = Highpass, 1 = Lowpass)
       |   |   |   \------------------- Reserved (0)
       |   |   \----------------------- Filter Input (0 = On, 1 = Off)
       |   \-------------------------- Reserved (0)
       \-----------------------------

    DEFAULT
     011h, N/A

    SEE ALSO
     03Dh   Input Control Left                  Read/Write
     03Eh   Input Control Right                 Read/Write
------------------------------------------------------------------------------
 00Eh       Output/Stereo Select                        Read/Write  SBPro Only

    SELECT BYTE
     /===v===v===v===v===v===v===v===\
     I[7]|[6]| 5 |[4]|[3]|[2]| 1 |[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Reserved (1)
       |   |   |   |   |   |   \------- Stereo Output Mode (1 = Stereo)
       |   |   |   |   |   \---------- Reserved (0)
       |   |   |   |   \-------------
       |   |   |   \------------------- Reserved (1)
       |   |   \----------------------- Filter Output (0 = On, 1 = Off)
       |   \-------------------------- Reserved (0)
       \-----------------------------

    DEFAULT
     011h, N/A

    NOTES
     * SoundBlaster 16 uses command 0Bxh/0Cxh for stereo output.

    SEE ALSO
     03Ch   Output Control                      Read/Write
------------------------------------------------------------------------------
 022h       Master Volume                               Read/Write  SBPro

    VOLUME BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Right Master bit  0  (SB16, SBPro=1)
       |   |   |   |   |   |   \------ Right Master bit 3-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Left  Master bit  0  (SB16, SBPro=1)
       |   |   \---------------------- Left  Master bit 3-1 (SBPro)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     011h, 0CCh

    NOTES
     * SoundBlaster 16 will automatically update registers 030h and 031h,
        transferring bits 7-4 and setting bit 3.
     * SoundBlaster Pro register 002h is the same as this.

    SEE ALSO
     002h   Master Volume                       Read/Write
     -----------------------------------------------------
     030h   Master Volume Left                  Read/Write
     031h   Master Volume Right                 Read/Write
------------------------------------------------------------------------------
 026h       FM Level                                    Read/Write  SBPro

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Right FM Level bit  0  (SB16, SBPro=1)
       |   |   |   |   |   |   \------ Right FM Level bit 3-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Left  FM Level bit  0  (SB16, SBPro=1)
       |   |   \---------------------- Left  FM Level bit 3-1 (SBPro)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     011h, 0CCh

    NOTES
     * SoundBlaster 16 will automatically update registers 033h and 034h,
        transferring bits 7-4 and setting bit 3.
     * SoundBlaster Pro will automatically update register 006h,
        transferring bits 3-1 and setting bit 0.

    SEE ALSO
     006h   FM Output Control                   Read/Write
     -----------------------------------------------------
     034h   FM Level Left                       Read/Write
     035h   FM Level Right                      Read/Write
------------------------------------------------------------------------------
 028h       CD Audio Level                              Read/Write  SBPro

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Right CD Audio bit  0  (SB16, SBPro=1)
       |   |   |   |   |   |   \------ Right CD Audio bit 3-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Left  CD Audio bit  0  (SB16, SBPro=1)
       |   |   \---------------------- Left  CD Audio bit 3-1 (SBPro)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     011h, 000h

    NOTES
     * SoundBlaster 16 will automatically update registers 035h and 036h,
        transferring bits 7-4 and setting bit 3.

    SEE ALSO
     036h   CD Audio Level Left                 Read/Write
     037h   CD Audio Level Right                Read/Write
------------------------------------------------------------------------------
 02Eh       Line In Level                               Read/Write  SBPro

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Right Line In bit  0  (SB16, SBPro=1)
       |   |   |   |   |   |   \------ Right Line In bit 3-1 (SBPro)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------- Left  Line In bit  0  (SB16, SBPro=1)
       |   |   \---------------------- Left  Line In bit 3-1 (SBPro)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     011h, 000h

    NOTES
     * SoundBlaster 16 will automatically update registers 037h and 038h,
        transferring bits 7-4 and setting bit 3.

    SEE ALSO
     038h   Line In Level Left                  Read/Write
     039h   Line In Level Right                 Read/Write
------------------------------------------------------------------------------
 030h       Master Volume Left                          Read/Write  SB16

    VOLUME BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Left Master Volume (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 0C0h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 7-4
        of register 022h
     * SoundBlaster Pro selects register 020h for 030h.

    SEE ALSO
     031h   Master Volume Right                 Read/Write
     -----------------------------------------------------
     022h   Master Volume                       Read/Write
------------------------------------------------------------------------------
 031h       Master Volume Right                         Read/Write  SB16

    VOLUME BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Right Master Volume (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 0C0h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 3-0
        of register 022h.

    SEE ALSO
     030h   Master Volume Left                  Read/Write
     -----------------------------------------------------
     022h   Master Volume                       Read/Write
------------------------------------------------------------------------------
 032h       DAC Level Left                              Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Left DAC Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 0C0h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 7-4
        of register 024h.
     * SoundBlaster Pro selects register 022h for 032h.

    SEE ALSO
     033h   DAC Level Right                     Read/Write
     -----------------------------------------------------
     004h   DAC Level                           Read/Write
------------------------------------------------------------------------------
 033h       DAC Level Right                             Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Right DAC Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 0C0h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 3-0
        of register 024h.

    SEE ALSO
     032h   DAC Level Left                      Read/Write
     -----------------------------------------------------
     004h   DAC Level                           Read/Write
------------------------------------------------------------------------------
 034h       FM Level Left                               Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Left FM Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 0C0h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 7-4
        of register 026h.

    SEE ALSO
     035h   FM Level Right                      Read/Write
     -----------------------------------------------------
     006h   FM Output Control                   Read/Write
     026h   FM Level                            Read/Write
------------------------------------------------------------------------------
 035h       FM Level Right                              Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Right FM Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 0C0h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 3-0
        of register 026h.

    SEE ALSO
     034h   FM Level Left                       Read/Write
     -----------------------------------------------------
     006h   FM Output Control                   Read/Write
     026h   FM Level                            Read/Write
------------------------------------------------------------------------------
 036h       CD Audio Level Left                         Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Left CD Audio Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 7-4
        of register 028h.
     * SoundBlaster Pro selects register 026h for 036h.

    SEE ALSO
     037h   CD Audio Level Right                Read/Write
     -----------------------------------------------------
     028h   CD Audio Level                      Read/Write
------------------------------------------------------------------------------
 037h       CD Audio Level Right                        Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Right CD Audio Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 3-0
        of register 028h.

    SEE ALSO
     036h   CD Audio Level Left                 Read/Write
     -----------------------------------------------------
     028h   CD Audio Level                      Read/Write
------------------------------------------------------------------------------
 038h       Line In Level Left                          Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Left Line In Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 7-4
        of register 02Eh.
     * SoundBlaster Pro selects register 028h for 038h.

    SEE ALSO
     039h   Line In Level Right                 Read/Write
     -----------------------------------------------------
     02Eh   Line In Level                       Read/Write
------------------------------------------------------------------------------
 039h       Line In Level Right                         Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Right Line In Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * SoundBlaster 16 will automatically transfer bits 7-4 to bits 3-0
        of register 02Eh.

    SEE ALSO
     038h   Line In Level Left                  Read/Write
     -----------------------------------------------------
     02Eh   Line In Level                       Read/Write
------------------------------------------------------------------------------
 03Ah       Microphone Level                            Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 | 3 |[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------- Microphone Level (2dB)
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 000h

    SEE ALSO
     00Ah   Microphone Level                    Read/Write
------------------------------------------------------------------------------
 03Bh       PC Speaker Level                            Read/Write  SB16

    LEVEL BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 |[5]|[4]|[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------- PC Speaker Level (2dB)
       \-----------------------------

    DEFAULT
     N/A, 000h
------------------------------------------------------------------------------
 03Ch       Output Control                              Read/Write  SB16

    CONTROL BYTE
     /===v===v===v===v===v===v===v===\
     I[7]|[6]|[5]| 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Microphone     (0 = Off, 1 = On)
       |   |   |   |   |   |   \------- Right CD Audio (0 = Off, 1 = On)
       |   |   |   |   |   \----------- Left  CD Audio (0 = Off, 1 = On)
       |   |   |   |   \--------------- Right Line In  (0 = Off, 1 = On)
       |   |   |   \------------------- Left  Line In  (0 = Off, 1 = On)
       |   |   \---------------------- Reserved (0)
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 01Fh

    SEE ALSO
     041h   Output Gain Control Left            Read/Write
     042h   Output Gain Control Right           Read/Write
     -----------------------------------------------------
     036h   CD Audio Level Left                 Read/Write
     037h   CD Audio Level Right                Read/Write
     038h   Line In Level Left                  Read/Write
     039h   Line In Level Right                 Read/Write
     03Ah   Microphone Level                    Read/Write
     -----------------------------------------------------
     00Eh   Output/Stereo Select                Read/Write
------------------------------------------------------------------------------
 03Dh       Input Control Left                          Read/Write  SB16

    CONTROL BYTE
     /===v===v===v===v===v===v===v===\
     I[7]| 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Microphone     (0 = Off, 1 = On)
       |   |   |   |   |   |   \------- Right CD Audio (0 = Off, 1 = On)
       |   |   |   |   |   \----------- Left  CD Audio (0 = Off, 1 = On)
       |   |   |   |   \--------------- Right Line In  (0 = Off, 1 = On)
       |   |   |   \------------------- Left  Line In  (0 = Off, 1 = On)
       |   |   \----------------------- Right FM       (0 = Off, 1 = On)
       |   \--------------------------- Left  FM       (0 = Off, 1 = On)
       \------------------------------- Reserved (0)

    DEFAULT
     N/A, 015h

    NOTES
     * Register controls remapping of left input channel
        (off, left, right, or left and right)

    SEE ALSO
     03Eh   Input Control Right                 Read/Write
     -----------------------------------------------------
     03Fh   Input Gain Control Left             Read/Write
     -----------------------------------------------------
     034h   FM Level Left                       Read/Write
     035h   FM Level Right                      Read/Write
     036h   CD Audio Level Left                 Read/Write
     037h   CD Audio Level Right                Read/Write
     038h   Line In Level Left                  Read/Write
     039h   Line In Level Right                 Read/Write
     03Ah   Microphone Level                    Read/Write
     -----------------------------------------------------
     00Ch   Input/Filter Select                 Read/Write
------------------------------------------------------------------------------
 03Eh       Input Control Right                         Read/Write  SB16

    CONTROL BYTE
     /===v===v===v===v===v===v===v===\
     I[7]| 6 | 5 | 4 | 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Microphone     (0 = Off, 1 = On)
       |   |   |   |   |   |   \------- Right CD Audio (0 = Off, 1 = On)
       |   |   |   |   |   \----------- Left  CD Audio (0 = Off, 1 = On)
       |   |   |   |   \--------------- Right Line In  (0 = Off, 1 = On)
       |   |   |   \------------------- Left  Line In  (0 = Off, 1 = On)
       |   |   \----------------------- Right FM       (0 = Off, 1 = On)
       |   \--------------------------- Left  FM       (0 = Off, 1 = On)
       \------------------------------- Reserved (0)

    DEFAULT
     N/A, 00Bh

    NOTES
     * Register controls remapping of right input channel
        (off, left, right, or left and right)
     * SoundBlaster Pro selects register 02Eh for 03Eh.

    SEE ALSO
     03Dh   Input Control Left                  Read/Write
     -----------------------------------------------------
     040h   Input Gain Control Right            Read/Write
     -----------------------------------------------------
     034h   FM Level Left                       Read/Write
     035h   FM Level Right                      Read/Write
     036h   CD Audio Level Left                 Read/Write
     037h   CD Audio Level Right                Read/Write
     038h   Line In Level Left                  Read/Write
     039h   Line In Level Right                 Read/Write
     03Ah   Microphone Level                    Read/Write
     -----------------------------------------------------
     00Ch   Input/Filter Select                 Read/Write
------------------------------------------------------------------------------
 03Fh       Input Gain Control Left                     Read/Write  SB16

    GAIN BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 |[5]|[4]|[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------- Left Input Gain Control (2^x)
       \-----------------------------

    DEFAULT
     N/A, 000h

    SEE ALSO
     040h   Input Gain Control Right            Read/Write
     -----------------------------------------------------
     043h   Automatic Gain Control (AGC)        Read/Write
     -----------------------------------------------------
     03Dh   Input Control Left                  Read/Write
------------------------------------------------------------------------------
 040h       Input Gain Control Right                    Read/Write  SB16

    GAIN BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 |[5]|[4]|[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------- Right Input Gain Control (2^x)
       \-----------------------------

    DEFAULT
     N/A, 000h

    SEE ALSO
     03Fh   Input Gain Control Left             Read/Write
     -----------------------------------------------------
     043h   Automatic Gain Control (AGC)        Read/Write
     -----------------------------------------------------
     03Dh   Input Control Right                 Read/Write
------------------------------------------------------------------------------
 041h       Output Gain Control Left                    Read/Write  SB16

    GAIN BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 |[5]|[4]|[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------- Left Output Gain Control (2^x)
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * Output Gain Control has no effect when internal amplifier disabled.

    SEE ALSO
     042h   Output Gain Control Right           Read/Write
     -----------------------------------------------------
     03Ch   Output Control                      Read/Write
------------------------------------------------------------------------------
 042h       Output Gain Control Right                   Read/Write  SB16

    GAIN BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 |[5]|[4]|[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------- Right Output Gain Control (2^x)
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * Output Gain Control has no effect when internal amplifier disabled.

    SEE ALSO
     041h   Output Gain Control Left            Read/Write
     -----------------------------------------------------
     03Ch   Output Control                      Read/Write
------------------------------------------------------------------------------
 043h       Automatic Gain Control (AGC)                Read/Write  SB16

    AGC BYTE
     /===v===v===v===v===v===v===v===\
     I[7]|[6]|[5]|[4]|[3]|[2]|[1]| 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- Automatic Gain Control (1 = Enable)
       |   |   |   |   |   |   \------ Reserved (0)
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \-----------------
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 000h

    NOTES
     * Automatic Gain Control automatically maximizes input signal strength.

    SEE ALSO
     03Fh   Input Gain Control Left             Read/Write
     040h   Input Gain Control Right            Read/Write
------------------------------------------------------------------------------
 044h       Treble Left                                 Read/Write  SB16

    TREBLE BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 |[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------ Treble Left (2dB, -14dB to 14dB)
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 080h

    SEE ALSO
     045h   Treble Right                        Read/Write
     -----------------------------------------------------
     046h   Bass Left                           Read/Write
------------------------------------------------------------------------------
 045h       Treble Right                                Read/Write  SB16

    TREBLE BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 |[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------ Treble Right (2dB, -14dB to 14dB)
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 080h

    SEE ALSO
     044h   Treble Left                         Read/Write
     -----------------------------------------------------
     047h   Bass Right                          Read/Write
------------------------------------------------------------------------------
 046h       Bass Left                                   Read/Write  SB16

    BASS BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 |[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------ Bass Left (2dB, -14dB to 14dB)
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 080h

    SEE ALSO
     047h   Bass Right                          Read/Write
     -----------------------------------------------------
     044h   Treble Left                         Read/Write
------------------------------------------------------------------------------
 047h       Bass Right                                  Read/Write  SB16

    BASS BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 |[3]|[2]|[1]|[0]I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \-- Reserved (0)
       |   |   |   |   |   |   \-----
       |   |   |   |   |   \---------
       |   |   |   |   \-------------
       |   |   |   \------------------ Bass Right (2dB, -14dB to 14dB)
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    DEFAULT
     N/A, 080h

    SEE ALSO
     046h   Bass Left                           Read/Write
     -----------------------------------------------------
     045h   Treble Right                        Read/Write
------------------------------------------------------------------------------
 080h       IRQ Select                                  Read/Write  SB16

    SELECT BYTE
     /===v===v===v===v===v===v===v===\
     I[7]|[6]|[5]|[4]| 3 | 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- IRQ2  (0 = Disable, 1 = Enable)
       |   |   |   |   |   |   \------- IRQ5  (0 = Disable, 1 = Enable)
       |   |   |   |   |   \----------- IRQ7  (0 = Disable, 1 = Enable)
       |   |   |   |   \--------------- IRQ10 (0 = Disable, 1 = Enable)
       |   |   |   \------------------ Reserved (1)
       |   |   \---------------------
       |   \-------------------------
       \-----------------------------

    NOTES
     * Unaffected by mixer reset or soft reboot.
     * Enabling multiple bits enables multiple IRQs.

    SEE ALSO
     081h   DMA Select                          Read/Write
     -----------------------------------------------------
     082h   IRQ Status                          Read
------------------------------------------------------------------------------
 081h       DMA Select                                  Read/Write  SB16

    SELECT BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 |[4]| 3 |[2]| 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- DMA0, 8-bit  (0 = Disable, 1 = Enable)
       |   |   |   |   |   |   \------- DMA1, 8-bit  (0 = Disable, 1 = Enable)
       |   |   |   |   |   \----------- DMA2, Reserved (0)
       |   |   |   |   \--------------- DMA3, 8-bit  (0 = Disable, 1 = Enable)
       |   |   |   \------------------- DMA4, Reserved (0)
       |   |   \----------------------- DMA5, 16-bit (0 = Disable, 1 = Enable)
       |   \--------------------------- DMA6, 16-bit (0 = Disable, 1 = Enable)
       \------------------------------- DMA7, 16-bit (0 = Disable, 1 = Enable)

    NOTES
     * Unaffected by mixer reset or soft reboot.
     * Enabling multiple 8 or 16-bit DMA bits enables multiple DMA channels.
     * Disabling all 8-bit DMA channel bits disables 8-bit DMA requests,
        including translated 16-bit DMA requests.
     * Disabling all 16-bit DMA channel bits enables translation of 16-bit DMA
        requests to 8-bit ones, using the selected 8-bit DMA channel.

    SEE ALSO
     080h   IRQ Select                          Read/Write
------------------------------------------------------------------------------
 082h       IRQ Status                                  Read        SB16

    STATUS BYTE
     /===v===v===v===v===v===v===v===\
     I 7 | 6 | 5 | 4 |[3]| 2 | 1 | 0 I
     \=v=^=v=^=v=^=v=^=v=^=v=^=v=^=v=/
       |   |   |   |   |   |   |   \--- IRQ Status, 8-bit   (1 = Active)
       |   |   |   |   |   |   \------- IRQ Status, 16-bit  (1 = Active)
       |   |   |   |   |   \----------- IRQ Status, MPU-401 (1 = Active)
       |   |   |   |   \--------------- Reserved (0)
       |   |   |   \------------------ ???
       |   |   \---------------------  (01h = v4.04, 02h = v4.05, 08h = v4.12)
       |   \-------------------------
       \-----------------------------

    SEE ALSO
     080h   IRQ Select                          Read/Write